Die for cutting taper threads



DIE FOR CUTTING TAPER THREADS Filed June 22, 1940 3 Sheets-Sheet l E5 INVENTOR i HTTo NEY Feb; 3, 1942. w. J. HOGG 2,271,641

DIE FOR CUTTING TAPER THREADS 5 Sheets-Sheet 2 Filed June 22, 1940 Feb. 3, 1942. w HO Y 2,271,641

DI OR CUTTING TAPER THREADS I Patented eh. 3, 1942 DIE FOR CUTTING TAPER THREADS William J. Hogg, Cleveland, Ohio, assignor to The National Acme Company, Cleveland, Ohio, a

corporation of Ohio Application June 22, 1940, Serial No. 341,878 r 20 Claims.

This invention relates to threading tools or dies and more particularly'to that type thereof adapted to cut tapered or expanding threads on the work and has for its principal object the provision of an improved die simple in construction, eflicient in operation, accurate inuse, inexpensive to manufacture, simple to assemble and containing a minimum number of parts which may be readily replaced.

' A further object of the invention is the combination with a tapered threading die of improved chaser tripping means for rapidly expanding the chasers out of the work upon completion of the thread cutting operation.

In the drawings accompanying and forming a part of this specification,

Fig. 1 is a vertical section through this improved die.

Fig. 2 is a horizontal section on the line 2-2 of Fig. 1.

Fig. 3 is a front elevation of Fig. 1 showing the position of the chasers.

Fig. 4 is a transverse section on line 4-4 of Fig. 1, illustrating the cam controlling means for actuating the chasers.

Fig. 5 is a similar transverse sectionon line 55 of Fig. 1, illustrating the spring actuated cam controlling means.

Fig. 6 is a similar transverse section on line 66 of Fig. 1, illustrating the adjusting segment or key for controlling the size adjustment.

Fig. 7 is a plan view of the same mechanism including a part of the die body, and

Fig. 8 is a plan View of the sleeve member illustrating the spiral slot and the cam engaged therewith for effecting its rotation and the key located in its outer periphery for controlling rotation of the outer sleeve.

Similar characters of reference indicate corresponding parts in the several Views.

Before explaining in detail the present improvement and its mode of operation, I desire to have it understood that the invention is not limited to the details of construction and arrangement of parts illustrated in the accompanying drawings since the invention is capable a core piece I having at its forward end an adjustable work engaging nose piece 8. Carried by this core 1 is a cross bar 9 extending through horizontal slots ill in the die body 2 and provided at its ends with cams l I adapted to engage spiral slots 12' on the inner periphery of a rotatable sleeve [3 carried on the outside of the body 2.

A sleeve I4 is slidably mounted on the exterior of this sleeve 13 and secured against independent relative rotation by a key (5 projecting into longitudinal slots Hi on the inner wall of the sleeve M. v

Adjustably carried at the forward end of the sleeve I 4 is a key or segment I! which extends into a slot l8 of a rotatable taper control ring l9 having a circumferentially located spring 20 under constant tension.

In the forward end of this taper control ring I9 is located a series of spiral cam slots 2| for engagement with pins 22 of the chaser blocks 5. The rotation of the taper control ring will move the chasers radially inwardly or outwardly. Thus, circumferential movement of the segment I! rotates the ring l9 and adjusts the position of the chasers radially for controlling the size of thread.

Toward the rear of the sleeve 14 pins 23 are secured which extend into the spiral slots I2 in position to be engaged by the ends of the cross bar 9 at the completion of the thread cutting operation.

The operation of the die is as follows:

The shank of the body member 2 is secured to the usual machine and either the die or the work may be fed forward but, in the present instance, the operation is described with the die fed forward by the usual lead screw of the machine While the work is held axially stationary. Either the work or the die may be rotated.

As the die is fed toward the work, the adjustable work engaging member contacts the end of the work and stops the forward travel of the core I and bar 9. Continued forward travel of the remaining parts under the influence of the lead screw of the machine causes the cams II on theends of the bar 9 to slide along the spiral slots l2 and rotate the sleeve I3.

Rotation of the sleeve [deflects simultaneous rotation of the outer sleeve I4 and engagement of the key I! with the taper operating ring effects a like rotation of this ring which, in turn, causes the chaser block pins riding along the spiral slots 2| to move the chaser blocks 5 and chasers 6 radially outwardlyin the T-slots I of the body 2 to cut an expanding or tapered thread in the work.

When the desired length of thread has been cut, the bar 9 contacts the pins 23, stopping the forward travel of the outer sleeve l4, and the continued forward travel of the remaining parts causes the pins H to withdraw from the slots l8 of the control ring 19 whereupon this ring I9 is rapidly rotated under action of the spring 20 to expand the chasers out of the work.

To reset the die the operating ring is provided with a handle 24 and rotation of the ring by means of this handle against the action of the spring 20 will cause the slots I8 to be brought into line with the pins I1 whereupon the springs 25 move the outer sleeve forward. A spring 26 holds the core piece forward when the die is withdrawn from the work after the threading operation has been completed to permit resetting of the other parts.

It is to be understood that, by describing in detail herein any particular form, structure or arrangement it is not intended to limit the invention beyond the terms of the several claims or the requirements of the prior art.

Having thus explained the nature of my said invention and described a way of constructing and using the same although without attempting to set forth all of the forms in which it may be made or all of the modes of its use, I claim:

1. A threading tool for cutting tapered threads comprising a body member having radially shiftable chasers carried thereby, a member rotatable and axially shiftable relative to said body member, and a member rotatable with said last member and cooperating with said chasers for shifting the chasers gradually and rotatable independently thereof for rapidly shifting the chasers upon the axial shifting of said rotatable member.

2. A threading too1 for cutting tapered threads comprising a body member having radially shiftable chasers carried thereby, a rotatable member for shifting said chasers, and means for controlling the rotation of said rotatable member including a rotatable member and an axially movable member for rotating said last rotatable member.

3. A threading tool for cutting tapered threads comprising a body member having radially shiftable chasers carried thereby, and means for shifting the chasers including a spring actuated rotatable member, a rotatable member for controlling th rotation of said first rotatable member, and axially movable means for effecting rotation of said second rotatable member during the thread cutting operation.

4. A threading tool for cutting tapered threads comprising a body member having radially shiftable chasers carried thereby, and means for shifting the chasers including a spring actuated rotatable member, a rotatable member for controlling the rotation of said first rotatable member, and axially movable means for efiecting rotation of said second rotatable member during the thread cutting operation, said second rotatable member also having axial movement effective to release its control of the first rotatable member.

5. A threading tool for cutting tapered threads comprising a body member having radially shiftable chaserscarried thereby, and means for shifting the chasers including a spring actuated rotatable memben'a rotatable member for controlling the rotation of said first rotatable member, and axially movable means for efiecting rotation of said second rotatable member during the thread cutting operation, said second rotatable member also having axial movement controlled by the axially movable member and effective to release its control of the first rotatable member.

6. A threading tool for cutting tapered threads comprising a body member having radially shiftable chasers carried thereby, a rotatable member for shifting the chasers, a plurality of means for rotating said member, one of said means including a rotatable member and an axially shiftable member for rotating said last rotatable member.

'7. A threading tool for cutting tapered threads comprising a body member having radially shiftable chasers carried thereby, a rotatable member for shifting the chasers, a plurality of means for rotating said member, on of said means including a rotatable and axially shiftable member, and an axially shiftable member for rotating and shifting said rotatable and shiftable member.

8. A threading tool for cutting tapered threads comprising a body member having radially shiftable chasers carried thereby, a rotatable member for shifting the chasers, a plurality of means for rotating said member, one of said means including a rotatable and axially shiftable member, an axially shiftable member for rotating and shifting said rotatable and shiftable member, and means for adjusting said chasers radially.

9. A threading tool for cutting tapered threads comprising a body member having a bore therein, radially shiftable chasers carried by the body member, a work engaging member within the bore and axially movable relative to said body, a rotatable member for shifting said chasers, a plurality of members for rotating said rotatable member, means connecting said rotatable members, one of said rotatable members controlled by the work engaging member and rotatable during the thread cutting operation for gradually shifting the chasers and axially shiftable upon completion thereof to disconnect said first rotatable member and permit rapid rotation thereof to release the chasers from the work.

10. A threading tool for cutting tapered threads comprising a body member having a bore therein, radially shiftable chasers carried by the body member, a work engaging member within the bore and axially movable relative to said body, a rotatable member for shifting said chasers, a plurality of members for rotating said rotatable member, means connecting said rotatable members, one of said rotatabl members controlled by the Work engaging member and rotatable during the thread cutting operation for gradually shifting the chasers and axially shiftable upon completion thereof to disconnect said first rotatable member and permit rapid rotation thereof to release the chasers from the work, and means carried by said rotatable and shiftable members for adjusting the chasers radially.

11. A threading tool for cutting tapered threads comprising a body member having a bore therein, radially shiftable chasers carried by said body member, a Work engaging member carried within said bore and shiftable axially relative to said body member, a plurality of rotatable members carried on the exterior of said threads comprising a body member having a bore therein, radially shiftable chasers carried by said body member, a work engaging member carried within said bore and shiftable axially relative to said body member, a plurality of rotatable members carried on the exterior of said body member, one having cooperativ engagement with the chasers for shifting them gradually during the thread cutting operation and rapidly at the end thereof, the relative shifting movement between the body member and work engaging member controlling saidrotation, and another of said rotating members also having axial movement at the endof the thread cutting operation to permit the rapid rotation of said first rotatable member.

13'. A threading tool for cutting tapered threads comprising a body member having a bore therein, radially shiftable chasers carried by said body member, a work engaging member carried within said bore and shiftable axially relative tosaid body member, a plurality of rotatable members carried on the exterior of said body member, one having cooperative engagement with the chasers for shifting them gradually during the thread cutting operation and rapidly at the end thereof, the relative shifting movement between the body member and work engaging member controlling said rotation, another of said rotating members also having axial movement at the end of the thread cutting operation to permit rapid rotation of said first rotatable member and another of said rotatable members having spiral cam slots cooperating with cam members carried by said work engaging member.

14. A threading tool for cutting tapered threads comprising a body member having radially shiftable chasers carried thereby, means for shifting said chasers gradually during the threading operation and comprising a rotatable member and a rotatable and axially shiftable member disengageably connected, said last member axially shiftable upon completion of the threading operation to permit rapid shifting of the chasers,and means for controlling the operation of said rotatable members.

15. A threading tool for fcutting tapered threads comprising a body member having radially shiftable chasers carried thereby, a plurality of rotatable members, one constructed for rapid rotation, means connecting them together for shifting said chasers gradually during the thread cutting operation, one of said rotatable members and its connecting means shiftable axially upon completion of the thread cutting operation, the shifting thereof effective to permit the rapid rotation of said rapidly rotatable member thereby to rapidly shift said chasers.

rotatable member for shifting said chasers, a work engaging member shiftable axially relative to said body member, and rotatable means controlled by said work engaging member and having a disengageable connection with said rotatable member for controlling the rotation thereof and the shifting of the chasers gradually during the thread cutting operation upon the relative axial shifting of said body and work engaging member, said rotatable means shiftable axially upon completion of the thread cutting operation thereby to disengage its connection with the rotatable member and permit rapid rotation of said rotatable member for rapidly shifting the chasers.

17. A threading tool for cutting tapered threads. comprising a body member having radially shiftable chasers carried thereby, a plurality of rotatable members, one constructed for rapid rotation, means connecting them together for shifting the chasers gradually during the thread cutting operation, one of said rotatable members and its connecting means shiftable axially relative to said body member upon com pletion of the thread cutting operation, the shifting thereof effective to permit the rapid rotation of said rapidly rotatable member for rapidly shifting the chasers, and a work engaging member shiftable axially relative to said body member and cooperating with said rotatable members for controlling the rotation thereof and the shifting of the axially shiftable rotatable member.

18. A threading tool threads comprising a body having radially shiftable chasers carried thereby, a rotatable 16. A threading tool for cutting tapered threads comprising a body member having radially shiftable chasers carried thereby, a

member constructed for rapid rotation for shifting said chasers, a rotatable and axially shiftable member, and means connecting said members during the thread cutting operation and disengageable at the end thereof upon the axial shifting of said last rotatable member whereby said first rotatable member will rapidly rotate to shift the chasers.

19. A threading tool for cutting tapered threads comprising a body having radially shiftable chasers carried thereby, a rotatable member constructed for rapid rotation for shifting the chasers, a rotatable and axially shiftable member, means connecting said members during the thread cutting operation and disengageable at the end thereof upon the axial shifting of said last rotatable member whereby said first rotatable member Will rapidly rotate to shift the chasers, and means for rotating and shifting said axially shiftable member.

20. A threading tool for cutting tapered threads comprising a body having radially shiftable chasers carried thereby, a rotatable member constructed for rapid rotation for shifting the chasers, a rotatable and axially shiftable member, means connecting said members during the thread cutting operation and disengageable at the end thereof upon the axial shifting of said last rotatable member whereby said first rotatable member will rapidly rotate to shift the chasers, and means for rotating and shifting said axially shiftable member, said means including a member shiftable axially relative to said body member.

WILLIAM J. HOGG.

for cutting tapered 

